As you might expect, Johnson & Johnson makes a lot of money. Last year, the healthcare giant generated revenue totaling nearly $72 billion. Over the past decade, J&J raked in over $668 billion. To put that amount into perspective, consider that a stack of that many $1 bills would reach more than 45,000 miles into the sky -- close to one-fifth the distance to the moon.

But where does all that revenue come from? Here's how Johnson & Johnson makes most of its money.